The interest in air pollution modelling has shown substantial growth over the last five years. This was particularly evident by the increasing number of participants attending the NATO/CCMS International Technical Meetings on Air Pollution modelling and its Application. At the last meeting 118 papers and posters were selected from an abundance of submitted abstracts divided over five modelling topics: (i) model assessment and verification, including policy applications, (ii) air pollution modelling in coastal areas with emphasis on the mediterranean region, (iii) accidental atmospheric releases, including warning systems and regulations, (iv) modelling of global and long-range transport and (v) new developments in turbulent diffusion. A round-table discussion chaired by John Irwin (USA) and Jan Kretzschmar (Belgium) on the harmonization of air pollution models was attended by more than 50 scientists and is reported in these proceedings. The opening paper addressed the main issue of this conference: modelling over complex terrain. Of particular interest were coastal areas where the surface inhomogeneities introduce small-scale circulation and varying atmospheric stability, often combined with a complex topography. As the conference was located on the beautiful island of Crete, problems faced by the host nation, particularly Athens and its environs were obvious examples for consideration. These together with other regions with similar geographical features were addressed. Heavily populated and industrialized as they often are, air quality is generally poor there and emission regulations are desired. Obviously, a major task of air pollution dispersion modelling is to assist policy makers in formulating sensible regulations.

Air Quality Modeling in Complex Terrains

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UK Atmospheric Dispersion Modelling System

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An Improved Dispersion Model for Regulatory Use - The OML Model

p. 29

The CAR Model: Calculation of Air Pollution from Road Traffic, A Calculation Method for the Determination of Air Quality in City Streets in The Netherlands

p. 39

A Conceptual Framework for Evaluating the Performance of Grid-Based Photochemical Air Quality Simulation Models

p. 49

Regional Analysis of S Emission-Deposition Trends in North America from 1979 Through 1988

p. 57

Estimation of the Sulfur Emissions Trends in Europe Based on Measurements and Source-Receptor Matrices

p. 65

Weather Conditions during Air Pollution Episodes in Athens, Greece: An Overview of the Problem